Appetite, I hardly Know Her (Pt. 1)
During my Senior year at Cornell College, I decided to pursue the distinction of graduating with honors within the Biochemistry and Molecular Biology Department. To do so, one must conduct original research, produce a dissertation, and defend said thesis in front of an Honors Committee and the public. Unfortunately, due to COVID-19, I was never able to publicly present my research and thesis, so I figured I would write a quick article giving the 10,000 foot view of my Honors project. I believe a lot of you will find this information very useful, and hopefully can implement this information into your life, or the life of someone you know.
I do not plan on getting into the real nitty-gritty biochemistry in this article (if you want to learn more, you can contact me at Adam.Plotkin49@gmail.com and I can send you my 93 page Honors Thesis if you want a solid headache). I also suggest that if you haven’t already, go read my paper that is published in “Geriatric Nursing” here, before you dive into this article (it will give you a ton of great background).
To give a quick background, in the Summer of 2019 I was fortunate enough to be selected for a Research Assistant internship at a nursing home in Wisconsin. I worked under the guidance of Dr. Christine Kovach, the Director of Research in Aging at said nursing home. Dr. Kovach essentially gave me the reigns to conduct my own research study. After extensive research and discussion with Dr. Kovach, I realized that there is a glaring issue in the elderly community, and especially among elderly individuals residing in nursing homes (or long-term care homes). This problem, that many of you are probably unknowingly familiar with, is called The Anorexia of Aging. For simplicity reasons, this can be thought of as a disease and can be defined as a decrease in food intake with age (1).
Although a lot of my articles focus on the severe obesity epidemic we are dealing with, we also need to deal with the flip side, which runs rampant in the elderly community. For example, maybe you know of a loved one over the age of 65 who has suddenly drastically cut down their food consumption. This decline in food intake results in weight loss, malnutrition, sarcopenia (loss of skeletal muscle mass and function), physical frailty, and cachexia (weakness and wasting of the body due to severe chronic illness; 1,2). This is worrying of course, because all of these outcomes are associated with increased risk of mortality and morbidity (1,2).
Yet, many of us assume that this “natural wasting” is just a normal part of aging, but we couldn’t be more wrong. In fact, when we boil things down, the anorexia of aging has a multifactorial etiology (the cause, set of causes, or manner of causation of a disease or condition) such as physiological, emotional, social, and environmental changes. So if we can figure out what some of the causes of declined food intake are, we can potentially set up proper interventions to impede this physical wasting with age.
Prior to my study, it was estimated that about 85% of residents living in a long-term care facility suffer from some sort of anorexia of aging (1). For my study, I decided to focus on residents with dementia, as people with dementia are even more susceptible to declined food intake as the anorexia of aging progresses (3,4). For instance, individuals with dementia may suffer from memory-related problems (forgetting to eat), develop feeding apraxia (the inability to eat), have a diminished drive to eat, and may suffer from increased bouts of depression, agitation, and delusions (2, 4, 5, 6, 7). Now there are many other factors that make individuals with dementia more susceptible to weight loss with age (which I cover in my published paper), but I think you are starting to get the picture.
Through a deep-dive into the literature, I found that although a decline in food intake is quite prevalent in people with dementia, there haven’t been many interventions put into place to detect this decline early enough to make a considerable difference (8). Therefore, this lead me to my primary research question: What are the factors associated with decreased food intake and nutritional status in these long-term care facility residents with dementia? As I stated in my published paper, “Comprehension of the factors associated with food intake and nutritional status combined with proven intervention techniques may reduce the negative health outcomes of declined food intake.” Thus, I set out to conduct a secondary-analysis study of 82 long-term care residents with dementia. To do so, I utilized pre-recorded data (via nurses, doctors, social workers, etc), observations in the dining room, first-hand questionnaires of residents and staff members, and the consultation of several Nurse Practitioners and Medical Doctors to fill out medical history forms.
Now the results of the study are all laid out in my published paper, but I believe the following figure summarizes the results quite effectively:
Now there is a lot to take away from these results, but for the sake of time, I believe it is pertinent to focus on appetite (My paper goes into much more detail if you are interested). If we examine the results closely, we see that appetite is associated with both food intake and nutritional status, and that both food intake and nutritional status are associated with function in these long-term care residents with dementia.
Why is this significant? While it seems declined food intake and poor nutritional status cannot be easily prevented, the findings demonstrated that both are associated with some potentially reversible conditions, such as poor appetite. Therefore, early detection of changes in appetite may allow for a more swift implementation of proven interventions (psychological, appetite-stimulation, social, etc..) in pursuit of increasing food intake and correcting nutritional deficiencies. This study also demonstrated that food intake and nutritional status are associated with function. Thus, increased food intake and improved nutritional status are associated with this sub-set of elderly individuals being able to better perform activities of daily living (such as eating, bathing, dressing, using the bathroom, and physically moving).
Hence, now you can start to see how appetite is at the center of this whole thing. If we can catch changes in appetite early, we can hopefully improve food intake and nutritional status, which not only pulls the individual further away from sarcopenia, cachexia and other negative health outcomes, but can also potentially improve quality of life via enhancing the individual’s ability to perform activities of daily living.
Part 2 of this series will dive a bit deeper into the the biochemical implications surrounding this research (essentially a condensed version of my 93 page Honors Thesis!)
- J.E. MorleyAnorexia of ageing: a key component in the pathogenesis of both sarcopenia and cachexia. J Cachexia Sarcopenia Muscle, 8 (4) (2017), pp. 523–526, 10.1002/jcsm.12192
- F. Landi, R. Calvani, M. Toasato, et al.Anorexia of aging: risk factors, consequences, and potential treatments Nutrients, 8 (2) (2016), p. 69, 10.3390/nu8020069
- P.D. Sloane, J. Ivey, M. Helton, et al.Nutritional issues in long-term care J Am Med Dir Assoc, 9 (7) (2008), pp. 476–485, 10.1016/j.jamda.2008.03.005
- R. VisvanathanAnorexia of aging Clin Geriatr Med, 31 (3) (2015), pp. 417–427,
- J.L. Fieldhouse, A.S. Doorduijn, F.A. de Leeuw, et al.A Suboptimal Diet is Associated with Poorer Cognition: The NUDAD Project Nutrients, 12 (3) (2020), p. 703, 10.3390/nu12030703
- N. Musson, J. Kincaid, P. Ryan, et al.Nature, nurture, nutrition: interdisciplinary programs to address the prevention of malnutrition and dehydration Dysphagia, 5 (2) (1990), pp. 96–101, 10.1007/bf02412651
- A.D. Jadczak, R. VisvanathanAnorexia of aging-an updated short review J Nutr Health Aging, 23 (3) (2019), pp. 306–309, 10.1007/s12603–019–1159–0
- A. SanfordAnorexia of aging and its role for frailty Curr Opin Clin Nutr Metab Care, 20 (1) (2017), pp. 54–60
- Cox, N., Ibrahim, K., Sayer, A., Robinson, S., & Roberts, H. (2019). Assessment and Treatment of the Anorexia of Aging: A Systematic Review. Nutrients, 11(1), 144. doi: 10.3390/nu11010144